Phrasal verb
rule out
Definition
phrasal verb. to decide that something is not possible or to remove it from a list of options.
phrasal verb. to exclude a possibility, person, or cause from consideration. Transitive; the object may be a noun phrase or a clause.
Examples
“The doctor wants to rule out any serious illness.”
“After checking the security footage, the police were able to rule out the first suspect because he was at home.”
“While the initial data suggested a mechanical failure, the investigators cannot yet rule out the possibility of human error or external interference in the crash.”
Examples
simple
“The doctor wants to rule out any serious illness.”
contextual
“After checking the security footage, the police were able to rule out the first suspect because he was at home.”
complex
“While the initial data suggested a mechanical failure, the investigators cannot yet rule out the possibility of human error or external interference in the crash.”
Usage
commonly used with nouns like 'possibility', 'chance', or 'option'.
Teaching tip
useful for discussing problem-solving or medical diagnoses; highlight that it is often used in the negative ('cannot rule out').
Pitfall
We can rule out of that option.
We can rule out that option.
the particle 'out' is not followed by 'of' when used as a phrasal verb meaning to exclude.
Phrasal verb
Particles
out
Separability
optional
Pattern
rule (+ object) + out (+ object)
Synonyms
Antonyms
Grammar
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.B2 FirstIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.5.5–6.5TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 4.0–4.572–94TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.785–944
- Level
- B2 · Upper Intermediate
- Updated
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